| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2025-21781: batman-adv: fix panic during interface removal |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| batman-adv: fix panic during interface removal |
| |
| Reference counting is used to ensure that |
| batadv_hardif_neigh_node and batadv_hard_iface |
| are not freed before/during |
| batadv_v_elp_throughput_metric_update work is |
| finished. |
| |
| But there isn't a guarantee that the hard if will |
| remain associated with a soft interface up until |
| the work is finished. |
| |
| This fixes a crash triggered by reboot that looks |
| like this: |
| |
| Call trace: |
| batadv_v_mesh_free+0xd0/0x4dc [batman_adv] |
| batadv_v_elp_throughput_metric_update+0x1c/0xa4 |
| process_one_work+0x178/0x398 |
| worker_thread+0x2e8/0x4d0 |
| kthread+0xd8/0xdc |
| ret_from_fork+0x10/0x20 |
| |
| (the batadv_v_mesh_free call is misleading, |
| and does not actually happen) |
| |
| I was able to make the issue happen more reliably |
| by changing hardif_neigh->bat_v.metric_work work |
| to be delayed work. This allowed me to track down |
| and confirm the fix. |
| |
| [sven@narfation.org: prevent entering batadv_v_elp_get_throughput without |
| soft_iface] |
| |
| The Linux kernel CVE team has assigned CVE-2025-21781 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 5.4.291 with commit 167422a07096a6006599067c8b55884064fa0b72 |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 5.10.235 with commit ce3f1545bf8fa28bd05ec113679e8e6cd23af577 |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 5.15.179 with commit f0a16c6c79768180333f3e41ce63f32730e3c3af |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 6.1.129 with commit 7eb5dd201695645af071592a50026eb780081a72 |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 6.6.79 with commit 072b2787321903287a126c148e8db87dd7ef96fe |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 6.12.16 with commit 2c3fb7df4cc6d043f70d4a8a10f8b915bbfb75e7 |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 6.13.4 with commit 522b1596ea19e327853804da2de60aeb9c5d6f42 |
| Issue introduced in 4.6 with commit c833484e5f3872a38fe232c663586069d5ad9645 and fixed in 6.14 with commit ccb7276a6d26d6f8416e315b43b45e15ee7f29e2 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2025-21781 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| net/batman-adv/bat_v_elp.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/167422a07096a6006599067c8b55884064fa0b72 |
| https://git.kernel.org/stable/c/ce3f1545bf8fa28bd05ec113679e8e6cd23af577 |
| https://git.kernel.org/stable/c/f0a16c6c79768180333f3e41ce63f32730e3c3af |
| https://git.kernel.org/stable/c/7eb5dd201695645af071592a50026eb780081a72 |
| https://git.kernel.org/stable/c/072b2787321903287a126c148e8db87dd7ef96fe |
| https://git.kernel.org/stable/c/2c3fb7df4cc6d043f70d4a8a10f8b915bbfb75e7 |
| https://git.kernel.org/stable/c/522b1596ea19e327853804da2de60aeb9c5d6f42 |
| https://git.kernel.org/stable/c/ccb7276a6d26d6f8416e315b43b45e15ee7f29e2 |
